Title : The association of cycle threshold value with disease severity and biochemical outcomes among pediatric patients with rt-pcr confirmed covid-19 infection seen in a tertiary hospital
Abstract:
Background. The gold standard in the diagnosis of COVID-19 infection remains to be through RT-PCR. This is done through the determination of a cycle threshold value. There have been conflicting studies as to whether the cycle threshold value can also be used to determine disease severity and biochemical outcomes in patients with RT-PCR confirmed COVID-19 infection.
Objectives. This study aims to determine the association between the cycle threshold values with Disease Severity and Biochemical Outcomes among Pediatric Patients with RT-PCR Confirmed COVID-19 infection seen in SLMC-QC in the period March 2020 until July 2022
Study Design. This is an analytical cross-sectional study.
Methods. The study population consisted of symptomatic pediatric patients with RT-PCR confirmed COVID-19 infection. The cycle threshold values were compared with the disease severity and biochemical outcomes of each patient.
Statistical Analysis. Descriptive statistics was used to summarize the general and clinical characteristics of the participants. Determination of the relationship between CT values with severity of the disease was analyzed using Chi-square test. Determination of the relationship between biochemical outcomes with severity of the disease was analyzed using the Anova test.
Results. The study included 472 individuals with RT-PCR confirmed COVID-19 infection. Majority of them are classified to have high viral RNA RT-PCR or less than 25 (73.4%) while 13.3% of the remaining are either medium (25 to 30) or low (>30). There is significant association between disease severity and CT Value classification (p=.0252). Results show that a medium or low viral load is significantly associated with severe to critical severity, while mild to moderate is associated with high level (<25). A significant difference also exists on mean WBC when grouped according to CT level classification (p=.011). Results show that those who are classified as low have significantly higher mean WBC (8,616.3) than those who are classified as high (6825.7).
Conclusion. A medium or low CT value is observed to be associated with severe to critical COVID-19 disease whereas a high CT value is associated with mild to moderate disease. A low CT value was seen to be associated with higher white blood cell counts.
Keywords: cycle threshold value, COVID-19 infection, white blood cell count
Presentation Keypoints:
- Once an RT-PCR test is performed, it generates a value called the cycle threshold (CT value). At present, the CT-value is being used to measure viral load and disease activity. This study explores other uses for the CT-value, particularly, in depicting disease severity in COVID-19 Confirmed patients.
- Since a CT value is generated for every RT-PCR test for COVID, this will provide a practical and faster means of disease prognostication and would help clinicians in deciding on further management.
- The results of the study also show a correlation between white blood cell count and CT value. Since a Complete blood Count is a very simple and readily-available test, it can be a good tool in predicting disease severity in COVID-19 patients.
